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COURSE TOPIC

The Data Science Workflow: From Question to Evidence

Follow a reproducible data science process from a clear question and data checks to analysis, evaluation, and communication.

Part of course Data Science & Machine Learning Course
Difficulty Level
Beginner
Estimated Learning Time
60-90 minutes
OVERVIEW

About The Data Science Workflow: From Question to Evidence

A data science project starts with a question, not a model. Define what decision or understanding is needed, identify what data can answer it, and record assumptions before analysis begins.

LEARNING OUTCOMES

What You Will Learn

  • Turn a broad request into an answerable data question.
  • Inspect data quality and document preparation choices.
  • Communicate findings, uncertainty, and limitations clearly.
TOPIC GUIDE

Learn The Data Science Workflow: From Question to Evidence

Frame the question

Clarify the audience, decision, unit of analysis, time period, and evidence needed. A measurable question reduces the temptation to search for patterns without knowing what they mean.

Understand the data

Record where data came from, how it was collected, what each row represents, and which fields may be missing or inconsistent. Use public or synthetic data for practice and avoid personal records without proper authorization.

Prepare and explore

Check types, duplicates, missingness, ranges, and category definitions. Make cleaning decisions explicit. Use descriptive statistics and visualizations to inspect patterns, but distinguish a visible association from a causal explanation.

Model only when useful

A model is one possible tool, not the goal of every project. Compare against a simple baseline, choose metrics that fit the question, and validate with data that was not used to fit the model.

Communicate and reproduce

Summarize the result, uncertainty, assumptions, and limits. Keep code and steps organized so another person can reproduce the analysis and understand what evidence supports each conclusion.

PRACTICAL EXAMPLE

Example / Code

Example
Question: Which service categories changed most over time?
Unit: One synthetic service request
Checks: Dates, duplicates, missing category labels
Analysis: Monthly counts by category
Caveat: Counts do not explain why a change occurred
TRY IT YOURSELF

Practice Task

Apply what you learned with a practical activity.

Choose a small public or synthetic dataset. Write one answerable question, describe what a row means, list three data-quality checks, and draft a result statement that separates an observed pattern from a possible explanation.

TOOLKIT

Tools & Technologies

  • Python
  • Jupyter
  • Pandas
  • Git
READY FOR THE COMPLETE COURSE?

Go Beyond The Data Science Workflow: From Question to Evidence

Explore the complete Data Science & Machine Learning Course curriculum, practical training, learning path and course details.